1. Field of the Invention
This invention relates to a breeding facility used for the mass breeding of fish, commonly referred to as tropical fish or other marine life wherein a minimal amount of individual handling of the fish is accomplished through the controlled flow or passage of the fish through each or predetermined successively arranged tank means.
2. Description of the Prior Art
Present day breeding procedures for tropical or ornamental fish utilized on fish farms and like facilities commonly suffer from problems and disadvantages basically concerned with the extensive use of skilled labor, large space requirements and the utilization of time consuming techniques and procedures which result in relatively low yield as well as a limitation on the type of fish which can be domestically produced. When considering the breeding process of 1000 breeder units, the following techniques are frequently used in todays breeding facilities.
Breeders are commonly held in holding tanks which usually have approximately a 20 to 30 gallon capacity. One thousand breeding units require at least eighty holding tanks which, in turn, requires a relatively large amount of space or land being utilized in current day fish farms. The male and female breeders are held in separate tanks. The average number of fish in each holding tank is approximately 30 but will, of course, vary depending on size and/or species.
Since female breeders have individual ovulation cycles, it is necessary to determine which females are actually in ovulation. This determination can be made commercially only from the appearance of the female and it is generally impossible to make more than an educated estimate that the female is actually ready to spawn. This is not only time consuming but requires a person highly skilled in the knowledge of various species of fish to make an accurate determination. The condition of the breeders are examined by the one or more skilled operators required, and they are then removed from the holding tank with a net or like collecting device. The collected breeders are placed in a container temporarily until they are removed again with a net or like collecting device to respective breeding tanks where breeding actually takes place. The general or conventional capacity of these tanks is approximately five gallons in size.
The breeder unit, under proper conditions and depending upon the species, should normally start to spawn within 12 to 48 hours. Each breeder tank must be checked two or three times daily to see if spawning has actually occurred. As soon as spawning is completed, the breeding unit must be removed from the breeding tank to prevent cannibalism. This is done again, with a net or like collecting device, whereby the breeder unit is put in a temporary holding container and then back into the relatively permanent holding tank. The breeders are handled at least four times in each breeding cycle.
After the larva are hatched they attach themselves on the walls of the tank or in spawning substrata or lie on the bottom. When the fry are swimming and able to eat, the spawning substrata must be removed. At this point, most of the water is removed by a siphon with a sponge or similar filter means attached to prevent the fry from being removed along with the drainage water. Fry that are actually sucked against the sponge or filter means are frequently damaged resulting in a relatively low yield of healthy fish. The tank must be removed from the rack or container and the remaining water in the fry poured into a plastic bag and transferred to a maturing facility. This procedure must be repeated with each tank or approximately with one thousand tanks considering one thousand breeder units in a breeding cycle.
As set forth above, there are common disadvantages associated with the prior art and/or currently used system and facilities. Namely, only a portion of the female breeders will be put in the spawning tanks at the right time due to factors which are generally uncontrollable. Such factors include the fact that females not in ovulation will not spawn, females mated after ovulation will not be fertilized, and other commonly known but generally uncontrollable occurences. Fungi and protozoa spores are present in all water, but healthy eggs are able to repel them. White eggs, or eggs produced by breeders which are not fertilized, require incubation and are not able to repel such spores. Fungi and protozoa then attack the good eggs. In addition, it is a common occurence in some species that a female, not spawned in her ovulation period is not able to discharge or absorb the eggs and they become obstructed within the female. This prevents her from breeding, and eventually will cause death.
In addition, if the female is not in ovulation and does not want to spawn, the male may kill her in a small tank because there is no room for her to escape. An example of such species in which this commonly occurs is Barbus tetrazona. Some males may not be stimulated to spawn and some may be impotent. Since this is impossible to detect, a spawning cycle in an individual tank will be fruitless, thereby wasting both time and space. A common occurence in some species is the requirement of a female to be combined with more than one male for mating. In certain species a female will spawn only for a few hours and it will be days before she will spawn again. Any males combined with this female when she is not in the spawning period are wasted for the whole spawning period except for these few hours. This requires maintaining a five to one male to female ratio constantly over a prolonged period of time thereby wasting space, time and the breeders themselves. Similarly, with many fish, two males are used with one female just to insure the fertilization of all eggs, especially if the males are smaller than the females. This requires a general ratio of two to one males which, again, is often a waste of breeders as well as time and space.
Most fish are not fed in breeding tanks. One of the best foods is plankton, but it is generally too dangerous to use in a small tank operation because many species will attack the hanging larva and the fry. Frozen and dry food will sour and cause a build up of bacteria and protozoa which attack the eggs thereby reducing the usable yield. The use of filters is generally too costly for a large number of breeding tanks. The only other possible foods are Tubifex and Enchytreus but they are generally too expensive, both in purchasing cost and the labor necessary for distribution. Consequently, the fish in breeding tanks are frequently hungry which encourages cannibalism and, again, loss of usable yield for the breeders themselves.
A very important disadvantage in currently used facilities and procedures is the frequent handling required of the breeders themselves. As set forth above, the breeders in a common cycle must be handled at least four times which is very frequently harmful to the fish. Because of the mortality rate due to the frequent handling of such fish a large breeder reserve must be maintained in order to operate a successful farm with a reasonable yield production. This breeder reserve often must be 20% or greater.
Another large, single disadvantage commonly occuring with current day breeding facilities is the quality and quantity of labor required. The old prior art facilities and procedures requires at least one highly qualified person with knowledge of the physiology and ecology of fish in order to sex the breeder, make optimum estimate of ovulation period, recognize fish diseases, know when spawning is completed and also realize when the fry should be removed. In addition, two responsible people with common knowledge of fish such as being able to recognize species and common fish diseases are also required for handling and periodic checking. Transferring of breeders and/or tanks requires an additional two or three laborers per thousand breeding tank cycle. Again, for the quantity of breeders and facilities set forth above, approximately 100 hours are utilized in both skilled and semi-skilled labor with current breeding methods.
Accordingly, there is an obvious need in the ornamental fish breeding industry for both facilities and techniques requiring much less utilization of both skilled and semi-skilled labor as well as physical facilities requiring much less space, etc. In order to overcome the current disadvantages, such a system should ideally take advantage of nature's provision for breeding fish such as breeding fish in large "schools" wherein specific ratios required are eliminated, manual handling of the fish is reduced or completely eliminated and a minimal amount of time is required for checking or observation by a highly skilled attendant.